The present invention relates generally to vehicle control switches for use in motor vehicles and, more particularly, to a system and method for providing a vehicle switch having a capacitive touch redundancy feature that enables actuation of the switch. The capacitive touch redundancy feature is employed on critical and safety related vehicle control switches such that actuation of the switches is controlled with the capacitive touch redundancy feature, thereby preventing accidental actuation of the switches.
In specialty vehicle markets—such as heavy trucks, agricultural equipment, and construction equipment, for example—electrical switches are used as control switches for a variety of applications, including general vehicle features/applications (e.g., switching the motor vehicle lighting, the windshield wipers, the rear windshield heating, the cruise control functions, etc., on and off) and critical or safety related vehicle features/applications (e.g., power take-off (PTO) switches, “e-stop” type switches, etc.). The critical and safety related control switches in such vehicles often include some sort of redundancy feature it which two separate actions are required by an operator to actuate the switch, so as to prevent accidental actuation of the switch.
For purposes of illustration of how such a redundancy feature is typically implemented, a PTO switch that is found on heavy trucks, agricultural equipment, and construction equipment is discussed here below. Standard PTO switches are configured to have a redundancy requirement for actuation, with PTO switches typically being designed to address the dual actuation/redundancy requirement by mechanical means. For example, existing PTO switches often require an operator to pull the PTO switch lever up before moving it up, to lift a cover before actuation of the switch, or to slide a locking mechanism before pressing the switch. While such dual mechanical actuations are adequate and effective for purposes of preventing accidental actuation of the PTO switch, the motions required for performing the dual mechanical actuations are often awkward and/or uncomfortable for an operator, as they are not ergonomic movements.
It would therefore be desirable to design a control switch for critical or safety related vehicle features/applications (e.g., PTO switch) that includes a redundancy feature having superior ergonomics as compared to existing switches that require dual actuation by mechanical means. It would further be desirable for such a control switch to provide superior ergonomics and ease of dual actuation without comprising the safety features of the switch, by still providing complete protection against accidental actuation of the switch.